Turner had 57 percent of the vote compared to Tony Buzbee's 43 percent.
FULL SPEECH: Sylvester Turner declares victory in runoff
Turner was elected Mayor of Houston in 2015 after he defeated Bill King in the closest mayoral election in Houston history by percentage.
He and his team were ecstatic as the results poured in.
LIVE ELECTIONS RESULTS: Keep tally on the latest vote reporting.
"If there's any lesson from this campaign, it is you don't have to have as much money as somebody else. You don't have to live in a house that's as big as somebody else. You don't have to drive a car that is as fancy as somebody else. And you can still compete in the same race, and you can win," Turner exclaimed to his supporters.
Tony Buzbee: 'We did not lose, we ran out of time.'
Buzbee stayed strong, saying his team didn't lose, they just ran out of time. "I'm not mad. I'm not bitter. I'm not discouraged," he said in a room full of his supporters.
Buzbee told supporters he will wait until Sunday morning to make a concession speech, holding out hope for final voting returns.
You can also watch ABC13's live coverage of the Election Night returns in the video above.
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